The Ras family of GTPases in cancer cell invasion

The ability of tumoral cells to invade surrounding tissues is a prerequisit e for metastasis. This is the most life-threatening event of tumor progress ion, and so research is intensely focused on elucidating the mechanisms res ponsible for invasion and metastasis. The Ras superfamily of GTPases compri ses several subfamilies of small GTP-binding proteins whose functions inclu de the control of proliferation, differentiation, and apoptosis. as well as cytoskeleton organization. The development of metastasis is a multistep pr ocess that requires coordinated activation of proliferation, motility, chan ges in normal cell-to-cell and cell-to-substrate contacts, degradation of e xtracellular matrix, inhibition of apoptosis, and adaptation to an inapprop riate tissue environment. Several members of the Ras superfamily of protein s have been implicated in these processes. The present review summarizes th e current knowledge in this field.